628694391 has 32 divisors (see below), whose sum is σ = 957942720. Its totient is φ = 363331584.

The previous prime is 628694329. The next prime is 628694413. The reversal of 628694391 is 193496826.

It is not a de Polignac number, because 628694391 - 2⁶ = 628694327 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 628694391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628694191) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 445495 + ... + 446903.

It is an arithmetic number, because the mean of its divisors is an integer number (29935710).

Almost surely, 2^628694391 is an apocalyptic number.

628694391 is a deficient number, since it is larger than the sum of its proper divisors (329248329).

628694391 is a wasteful number, since it uses less digits than its factorization.

628694391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2115.

The product of its digits is 559872, while the sum is 48.

The square root of 628694391 is about 25073.7789533209. The cubic root of 628694391 is about 856.6692835206.

The spelling of 628694391 in words is "six hundred twenty-eight million, six hundred ninety-four thousand, three hundred ninety-one".